Kinetics of synthesis olivine LiFePO4 by using a precipitated-sintering method

Abstract

The LiFePO4 precursor was synthesized using a precipitation with raw materials LiOH·H2O, (NH4)2HPO4 and FeSO4·7H2O. The kinetics of synthesis olivine LiFePO4 was studied by using a differential thermal analysis (DTA) at different heating rates. The average activation energy of the reaction where the precursor form olivine LiFePO4 was 239.39 kJ mol−1, calculated by Doyle–Ozawa and Kissinger methods. The reaction order, frequency factor, rate equation and kinetic equation of the reaction were determined by the Kissinger method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FTIR). The sample synthesized by the precursor sintered for 6 h at 550 °C shows a single-phase, regular morphology, well-distributed particle sizes and good electrochemical properties.